1. Field of the Invention
The present invention relates to an electromagnetic relay and a method for adjusting the armature of such a relay during manufacture, and in particular to an electromagnetic relay having a spring armature with a free end movable with respect to at least one cooperating pole plate and fixed end secured to the coil body at a coil flange thereof.
2. Description of the Prior Art
An electromagnetic relay having a tongue armature with a free end movable with respect to at least one pole plate and having a fixed end connected to a coil flange of the coil body is described in German AS No. 27 01 230. The resilient armature in that relay is connected to a carrier at the mounted end thereof, the carrier forming an adjustment plate which can be permanently deformed by means of an externally applied magnetic field in order to adjust the position of the armature. Such adjustment can be undertaken after the relay has been completely encapsulated after casting, however, the volume required for the adjustment plate must be incorporated in the design of the relay, which places a limit on miniaturization of the relay because the coil diameter cannot be made arbitrarily small. Moreover, the free spring length of the tongue armature in this conventional relay is limited by the interior volume of the coil body.
A relay having a spring-elastic tongue armature disposed inside the coil body is also known from German AS No. 19 09 940. The fastened end of the tongue armature of that relay is welded to a nose of a terminal pin. Adjustment of this relay is possible only by mechanically bending the armature at the location of the nose by means of an externally applied tool. The free spring length is also limited by the length of the hollow interior of the coil body.
The general concept of adjusting the position of a relay armature by irradiating the armature with thermal pulses is disclosed in German OS No. 29 18 100.